I saw THIRTEEN GHOSTS in its initial release and had my Ghost Viewer there the entire film. It worked quite well, since the screen went blue when the ghosts were to appear and if you looked through the blue cellophane, you did not see them. I looked through the red mostly. It was a cheap but effective gimmick.

Once I heard there was Smell-O-Vision that a movie had a scratch and sniff card to use in various scenes in the film [John Waters movie, was that right?] - but the best was probably that The Tingler and the seats wired for a "zap" whenever the tingler was onscreen (written about in Danse Macabre - Stephen King). Vincent Price I think was in the movie?